The present invention relates to a roofing shingle. More particularly, the present invention relates to a roofing shingle having a laying line that allows for proper positioning of multiple courses of shingles relative to one another, as well as proper spacing between the shingles on the same course.
The use of roofing shingles for protecting a roof is well known. Some man-made roofing products, such as composite slates, have been manufactured to resemble natural slate roofing. These man-made composite slate products may be a desirable alternative to natural slates given the fact that they are, in some cases, light weight, inexpensive and easy to apply. In addition, it is sometimes easy to control the color, weight, size and durability of man-made slates.
Installing composite slate roofing products on a roof begins with covering the roof deck with a waterproof underlayer. The slates are then placed on top of the waterproof underlayer and attached to the roof deck in rows or courses. In an effort to facilitate the process of fastening the slates to the roof deck, indentations or holes have been formed in composite slate products. In some cases, the indentations or holes may require an extra manufacturing step beyond the molding and/or cutting of the slate product, which may cause delays in manufacturing the slate product and increase production costs.
As best seen in FIG. 1, reference numeral 10 illustrates a prior art composite slate roofing product. In particular, composite slate roofing product 10 includes a thin laying line 12 positioned on a front surface 14, and a pair of nibs 16 that protrude from the left and right edges 18, 20 of roofing product 10. In addition, a shortened scale 22 includes a plurality of scale marks that extend inwardly from left edge 18, where one or more of scale marks may be labeled with numbers. For example, if scale mark 24 is labeled with the number “7”, and scale mark 24 is aligned with a top edge of an underlying roofing product, this would indicate that 7 inches of the butt portion of the underlying product will be exposed. Further, a pair of nail holes 26 may be formed in composite slate roofing product 10 at a position below the lower-most nibs 16.
The composite slates described above have been manufactured with very thin laying lines for purposes of aligning the numerous courses of slates on the roof relative to one another. For instance, a first course of shingles is first laid on the roof with thin laying line 12 located on front surface 14. A second course of shingles is then laid on top of the first course of shingles by placing either left edge 18 or right edge 20 directly atop or closely adjacent to the underlying thin laying line 12. The next shingle in the second course is generally laid next to the first shingle in the second course. This process continues until the second course of shingles extends to both edges of the roof. In the case where the composite slates do not include a thin laying line, horizontal and vertical lines are typically chalked on the waterproof underlayer to guide the application of the slates on the roof.
Despite the use of the aforementioned alignment guides, the application and alignment of shingles remains problematic: For example, the use of a thin laying line causes alignment problems when laying the second course of shingles on the roof. Specifically, the first shingle in the second course often covers up the entire laying line established by the first course when laid on top of the first course. By covering the entire laying line with the first shingle laid in the second course (or even after laying the first few shingles), the frame of reference for laying subsequent shingles in the second course then becomes the forward edge of the second course shingle. Therefore, it is very difficult to ensure that subsequent shingles laid in the second course are being properly positioned and aligned with the first course of shingles.
Accordingly, there exists a need for a roofing shingle that provides an adequate and convenient alignment guide for laying subsequent courses of shingles on a roof. The present invention fills these needs as well as other needs.